/*      $NetBSD: insdelln.c,v 1.25 2026/04/01 20:32:56 hgutch Exp $     */

/*
 * Copyright (c) 2000 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Julian Coleman.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: insdelln.c,v 1.25 2026/04/01 20:32:56 hgutch Exp $");
#endif                          /* not lint */

/*
 * Based on deleteln.c and insertln.c -
 * Copyright (c) 1981, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 */

#include <string.h>
#include <stdlib.h>

#include "curses.h"
#include "curses_private.h"

#ifndef _CURSES_USE_MACROS

/*
 * insdelln --
 *      Insert or delete lines on stdscr, leaving (cury, curx) unchanged.
 */
int
insdelln(int nlines)
{

        return winsdelln(stdscr, nlines);
}

#endif

/*
 * winsdelln --
 *      Insert or delete lines on the window, leaving (cury, curx) unchanged.
 */
int
winsdelln(WINDOW *win, int nlines)
{
        int     y, i, last;
        __LINE *temp;
#ifdef HAVE_WCHAR
        __LDATA *lp;
#endif /* HAVE_WCHAR */
        attr_t  attr;

        __CTRACE(__CTRACE_LINE,
            "winsdelln: (%p) cury=%d lines=%d\n", win,
            (win != NULL) ? win->cury : 0, nlines);

        if (__predict_false(win == NULL))
                return ERR;

        if (!nlines)
                return OK;

        if (__using_color && win != curscr)
                attr = win->battr & __COLOR;
        else
                attr = 0;

        if (nlines > 0) {
                /* Insert lines */
                if (win->cury < win->scr_t || win->cury > win->scr_b) {
                        /*  Outside scrolling region */
                        if (nlines > win->maxy - win->cury)
                                nlines = win->maxy - win->cury;
                        last = win->maxy - 1;
                } else {
                        /* Inside scrolling region */
                        if (nlines > win->scr_b + 1 - win->cury)
                                nlines = win->scr_b + 1 - win->cury;
                        last = win->scr_b;
                }
                for (y = last - nlines; y >= win->cury; --y) {
                        win->alines[y]->flags &= ~__ISPASTEOL;
                        win->alines[y + nlines]->flags &= ~__ISPASTEOL;
                        if (win->orig == NULL) {
                                temp = win->alines[y + nlines];
                                win->alines[y + nlines] = win->alines[y];
                                win->alines[y] = temp;
                        } else {
                                (void)memcpy(win->alines[y + nlines]->line,
                                    win->alines[y]->line,
                                    (size_t)win->maxx * __LDATASIZE);
                        }
                }
                for (y = win->cury - 1 + nlines; y >= win->cury; --y)
                        for (i = 0; i < win->maxx; i++) {
                                win->alines[y]->line[i].ch = win->bch;
                                win->alines[y]->line[i].attr = attr;
                                win->alines[y]->line[i].cflags |= 
                                    CA_BACKGROUND;
                                win->alines[y]->line[i].cflags &= 
                                    ~CA_CONTINUATION;
#ifdef HAVE_WCHAR
                                lp = &win->alines[y]->line[i];
                                if (_cursesi_copy_nsp(win->bnsp, lp) == ERR)
                                        return ERR;
                                lp->wcols = 1;
#endif /* HAVE_WCHAR */
                        }
                for (y = last; y >= win->cury; --y)
                        __touchline(win, y, 0, (int)win->maxx - 1);
        } else {
                /* Delete nlines */
                nlines = 0 - nlines;
                if (win->cury < win->scr_t || win->cury > win->scr_b) {
                        /*  Outside scrolling region */
                        if (nlines > win->maxy - win->cury)
                                nlines = win->maxy - win->cury;
                        last = win->maxy;
                } else {
                        /* Inside scrolling region */
                        if (nlines > win->scr_b + 1 - win->cury)
                                nlines = win->scr_b + 1 - win->cury;
                        last = win->scr_b + 1;
                }
                for (y = win->cury; y < last - nlines; y++) {
                        win->alines[y]->flags &= ~__ISPASTEOL;
                        win->alines[y + nlines]->flags &= ~__ISPASTEOL;
                        if (win->orig == NULL) {
                                temp = win->alines[y];
                                win->alines[y] = win->alines[y + nlines];
                                win->alines[y + nlines] = temp;
                        } else {
                                (void)memcpy(win->alines[y]->line,
                                    win->alines[y + nlines]->line,
                                    (size_t)win->maxx * __LDATASIZE);
                        }
                }
                for (y = last - nlines; y < last; y++)
                        for (i = 0; i < win->maxx; i++) {
                                win->alines[y]->line[i].ch = win->bch;
                                win->alines[y]->line[i].attr = attr;
                                win->alines[y]->line[i].cflags |= 
                                    CA_BACKGROUND;
                                win->alines[y]->line[i].cflags &= 
                                    ~CA_CONTINUATION;
#ifdef HAVE_WCHAR
                                lp = &win->alines[y]->line[i];
                                lp->wcols = 1;
                                if (_cursesi_copy_nsp(win->bnsp, lp) == ERR)
                                        return ERR;
#endif /* HAVE_WCHAR */
                        }
                for (y = win->cury; y < last; y++)
                        __touchline(win, y, 0, (int)win->maxx - 1);
        }
        if (win->orig != NULL)
                __id_subwins(win->orig);
        __sync(win);
        return OK;
}